Allegro is a multi-platform game library for C/C++ developers that provides many functions for graphics, sounds, player input (keyboard, mouse, and joystick), and timers. It also provides fixed and floating point mathematical functions, 3D functions, file management functions, compressed datafile, and a GUI.

The Catweasel Floppy Read/Write Tools are a set of tools for owners of Catweasel MK1 ISA and Catweasel MK3/MK4 PCI universal floppy disk controllers. cw2dmk reads several kinds of floppy disk, some of which ordinary PC controllers have trouble with, and save them in the DMK disk image format used by TRS-80 emulators. It can also handle any disk written using a Western Digital 177x/179x floppy disk controller, a PC-style NEC765-compatible controller, or a Digital Equipment Corporation RX02 controller. dmk2cw writes any DMK image back to a floppy. jv2dmk and dmk2jv3 convert images between DMK and JV1 and JV3 formats without requiring Catweasel hardware.

cingb is an attempt to write a Gameboy emulator for all kinds of platforms. It plays Gameboy and Gameboy Color ROMs, includes a debugger for step-by-step analysis of Gameboy programs and might be also interesting for educational purposes.

Cthugha displays your sound card's CD, line or
mic-input, then processes it into a hypnotic,
swirling, 256-color confection for your eyes.
Cthugha is available for MSDOS, Windows and Linux
and is distributed as shareware.

Dark Lands is a multiplayer RPG made fully with ANSI graphics. The source code is in Pascal. Currently, this game has probably no point except exploring the areas and killing monsters. It can be used as a BBS door game.

DeuTex is a wad composer for Doom, Heretic, Hexen and Strife. It can be used to extract the lumps of a wad and save them as individual files. Conversely, it can also build a wad from separate files. When extracting a lump to a file, it does not just copy the raw data, it converts it to an appropriate format (such as PPM for graphics, .au for samples, etc.). When it reads files for inclusion in pwads, it does the necessary reciprocal conversions. In addition, DeuTex has functions such as merging wads, etc.

distributed.net is a loosely knit group of computer users from all of the world that is taking up challenges requiring lots of computing power (most notably the RC5, DES, and OGR cracking contests). It is simple to participate in the challenges by downloading and running their client software (which uses idle CPU time to complete its tasks).